Hi Wido, I'm really interested in your script. Will you release it ? I'm sure I'm not the only one interested ;) If you need some help (testing or something else), don't hesitate to ask me. -- Thomas Lemarchand Cloud Solutions SAS - Responsable des systèmes d'information On jeu., 2014-12-18 at 15:47 +0100, Wido den Hollander wrote: > On 12/18/2014 03:37 PM, Sage Weil wrote: > > On Thu, 18 Dec 2014, Wido den Hollander wrote: > >> Hi, > >> > >> I've been playing around a bit with the recursive statistics for CephFS > >> today and I'm seeing some behavior with the rstats what I don't understand. > >> > >> I /A/B/C in my CephFS. > >> > >> I changed a file in 'C' and the ceph.dir.rctime xattr changed > >> immediately. I've been waiting for 60 minutes now, but /A and /A/B still > >> have their old rctime. > >> > >> A: 1418905422 (18-12-2014 13:23:42) > >> B: 1418905422 (18-12-2014 13:23:42) > >> C: 1418909134 (18-12-2014 14:25:34) > >> > >> It's 15:21:34 right now, so after 1 hour the rctime of A and B still > >> hasn't updated. > >> > >> How long does this take? I know the MDS is lazy in updating the rstats, > >> but one hour is quite long, isn't it? > > > > This is a bit of a loose end at the moment. The client doesn't have any > > refresh value for these stats. Right now an 'ls' in the parent dir will > > get you a fresh value, but repeatedly calling 'stat' will keep giving you > > the cached value. > > > > The ls didn't really trigger it for me. I'm using getfattr btw: > > $ getfattr -n ceph.dir.rctime /mnt/cephfs/A > > I unmounted and mounted and it worked right away. > > So this is probably not a real issue on a active filesystem where lots > of I/O on that client is happening, right? > > I'm building a PoC backup script which uses the rctimes to backup CephFS > in a reasonable way, not having rsync scan the whole tree. > > > I'm not sure what the right fix is. The normal inode fields are all > > perfectly accurate, and the protocol is built around making sure that's > > the case.. not giving "reasonably timely" values to the new stuff. :/ > > > > sage > > > > > -- > Wido den Hollander > 42on B.V. > Ceph trainer and consultant > > Phone: +31 (0)20 700 9902 > Skype: contact42on > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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